FIGS. 10A and 10B show a structure of a prior actuator and a method for driving the same.
As shown in FIG. 10A, the prior actuator 101 comprises a substrate 103, a first electrode 105, a piezoelectric layer 107, and a second electrode 109 in this order. A laminate 111 is composed of the substrate 103, the first electrode 105, the piezoelectric layer 107, and the second electrode 109. One end portion of the laminate 111 is immobilized with a support 113.
As shown in FIG. 10B, a potential difference is applied between the first electrode 105 and the second electrode 109 with a power source 121. The potential difference causes an electrostriction in the in-plane direction of the piezoelectric layer 107. As a result, the piezoelectric layer 107 is caused to be elongated along the X direction, whereas the substrate 103 is remained to be not elongated. Thus, the other end portion of the actuator 101 is displaced along the −Z direction.